C# Beginner here.
I'm making a 2D Tanks game, and everything's working out nicely so far.
Both of my tanks are Picture Boxes, and so is my Missile.
The image of the missile and tanks in the PictureBoxes have transparent BackColour properties. The problem is, the background of the missile & tanks are not transparent while on top of the other picturebox (pbBackground). It looks like this.
I'm aware that using different PB's is an inefficient way of going about it, but I've come pretty far and I don't really know any better. Anyways, as you can see, the Missile and Tank PB backgrounds show the form colour. When I downloaded the images, the backgrounds were transparent, I'm sure of it. How do I go about making the background of my PB's truly transparent? (Matching the background of the Overlapped PB?)
I saw this but it doesn't really match my scenario and I don't understand the solution.
UPDATE: Okay, I followed Tommy's advice, is this the right way to go about moving it along pbBackground in a timer constantly changing MissileX and MissileY? Currently this does nothing.
using (Graphics drawmissile = Graphics.FromImage(pbBackground.Image))
{
drawmissile.DrawImage(pbMissile.Image, new Point(MissileX,Convert.ToInt32(MissileY)));
}
PictureBox is opaque. And PictureBox is not efficient.
For making games, you should study Paint event which directly draws on your form.
Bitmap backgroundBitmap = new Bitmap("background");
Bitmap tankBitmap = new Bitmap("tank");
private void Form1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawImage(backgroundBitmap, 0, 0);
e.Graphics.DrawImage(tankBitmap, 30, 30);
}
private void timer1_Tick(object sender, EventArgs e)
{
this.Invalidate(); //trigger Form1_Paint to draw next frame
}
Don't layer multiple PictureBox instances on top of each other. It will get very confusing, very quickly.
Instead, use one single PictureBox and use Paint to draw your images to it. In this way, you can have much more control over the graphics operations happening.
Have a look at this
private void DrawIt()
{
System.Drawing.Graphics graphics = this.CreateGraphics();
System.Drawing.Rectangle rectangle = new System.Drawing.Rectangle(
50, 50, 150, 150);
graphics.DrawEllipse(System.Drawing.Pens.Black, rectangle);
graphics.DrawRectangle(System.Drawing.Pens.Red, rectangle);
}
In this example they demonstrate how to draw shapes directly onto a Form. You would use your PictureBox there instead. You can also draw images.
There's lots of ways to draw shapes onto a form using a System.Drawing.Graphics object. Try taking a look at this question for a comparison.
Tommy's answer is right, however, if you're dead set on using pictureboxes (a bad idea), set the overlapping picturebox backgroundcolour to Transparent and the Form's Background to whatever image. TIL the Transparent BackColour just uses the form colour / image. Tommy actually has the right answer here, but this is what I did to fix my problem (the lazy way).
Related
How could you - in WinForms - create a black area that (over time) loses/gains transparency and is redrawn constantly so a kind of transition is created? I dont want to create a seperate form, so this would be very helpful and I could rearrange my new items as soon as the black area reaches a transparency of 0.
Left: What i have what at the moment:
Right: What the program looks like on startup
What I would want: A totally black screen
Override the OnPaint method of the form, and fill a rectangle the size of the form with the desired transparency. In this example, transparency keeps increasing:
var transparency = 0;
protected override OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
// e.Graphics.DrawImage(Image, imageLeft, imageTop, imageWidth, imageHeight);
e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(transparency, Black)), this.ClientRectangle);
}
If you want to do this from a Timer event, inside the Tick event Invalidate the form to force the paint.
protected void MyTimer_Tick(object sender, eventArgs e) {
transparency++;
MyForm.Invalidate();
}
If you need to draw on top of the PictureBox, that presents a problem. One way to solve it is to get rid of the PictureBox and draw the image using Graphics.DrawImage before you draw the fade. If you want to show the image but have the black go up against the edges of your animal, then make it's background color of the PictureBox transparent and convert your image to use a PNG or GIF with all around the animal transparent in the original image.
For more complex effects, Check out the dot-net-transitions project on Google Code. It supports a variety of linear/non-linear transitions.
In my setup i have 5 pictureboxes which I am trying to layer.
My code for this is:
pbCoin1.Parent = pbMap;
pbCoin1.BackColor = Color.Transparent;
pbCoin2.Parent = pbMap;
pbCoin2.BackColor = Color.Transparent;
pbCoin3.Parent = pbMap;
pbCoin3.BackColor = Color.Transparent;
pbFlashlight.Parent = pbMap;
pbFlashlight.BackColor = Color.Transparent;`
All 5 pictureboxes contain images. The method I am using works fine, but the problem is that the PbCoin 1,2,3 are glitching trough my pbFLashlight(see image).
Can someone provide a solution such that the coins are only visible when the transparent part of the black layer is over it?
Don't use multiple picture boxes. Use a single PictureBox to represent the game area and handle the .Paint event. Do all of your drawing using GDI calls on the Graphics reference that .Paint sends you in e. You will want to call PictureBox.Invalidate at the end of the Paint event to cause it to queue up the next frame
For better performance, create a new Bitmap instance that you keep a reference to for the life of the game. Clear and do all your drawing to that bitmap every frame, then draw that bitmap to the PictureBox in .Paint.
For even better performance than that, don't use WinForms.
The basic pattern should look like this:
private void Canvas_Paint(object sender, PaintEventArgs e)
{
e.Graphics.DrawImage(...);
Canvas.Invalidate();
}
I need to allow to the user to draw lines over an bitmap. Lines should be drawn interactively, I mean something performed using typical code giving to the user a visual feedback about what is drawn:
private void MainPictureBox_MouseDown( object sender, MouseEventArgs e)
{
DrawingInProgress = true ;
Origin = new Point (e.X, e.Y);
}
private void MainPictureBox_MouseUp(object sender, MouseEventArgs e)
{
DrawingInProgress = false ;
}
private void MainPictureBox_MouseMove(object sender, MouseEventArgs e)
{
if (!DrawingInProgress) return ;
End = new Point (e.X, e.Y);
using( Pen OverlayPen = new Pen( Color .Red, 1.0f))
using (Graphics g = MainPictureBox.CreateGraphics())
{
g.DrawLine(OverlayPen, Origin, End);
}
}
Of course I keep track of the points using List.Add within MainPictureBox_MouseUp in order to draw lines in the Paint event (code not shown for the sake of simplicity)
Without the background image things could be done nicely simply overwriting the previous line with the background color, something like:
g.DrawLine(BackgroundColorPen, Origin, PreviousEnd);
g.DrawLine(OverlayPen, Origin, End);
but this is not possible with a not uniform background.
Invalidating the rectangle defined by the points: Origin, PreviousEnd then using Update() makes the rendering quite messy. I am wondering how to perform this task and those are possible ways to do so i am considering:
Draw the lines over a transparent bitmap then draw the bitmap over the Picturebox. I guess that with big images this is simply unfeasible for performances reason.
Using the Picture.BackgroundImage for the bitmap then drawing on the Picture.Image but I unable to figure out how this could really saave the day
Using double buffering? How?
Stacking a different control (a panel?) over the pictureBox, making it transparent (is it possible?) then drawing over it.
Could someone give a hint in the best direction? I am really getting lost.
The solutions working for me has been the following:
Create a transparent panel;
Put it over the bitmap having them overlap completely;
Draw on the panel using proper mouse events;
There is no need to cancel the previous shape, of course: it was a misleading question. It is sufficient to distinguish permanent shapes recorded in proper lists fed to the Paint event from the transient shape previously drawn that will be not drawn again in the next Paint event;
Make absolutely sure that all drawings are performed in the Paint event using the Graphics provided by the PaintEventArgs. Thanks to #HansPassant to have stressed this in a different post.
UPDATE: I took a break from messing with the transparency stuff for a few days. I started messing with it again tonight. I got a new result using Hans Passant's solution:
http://img3.imageshack.us/img3/4265/icontransp.jpg
Passant's solution does solve the issue of the transparent background gradient. However, I'm still running into the problem with the transparent colors in my icon blending with the form's BackColor. You can see the fuchsia around various parts of the icon in the above image.
ORIGINAL CONTENT:
I've been going at this for several hours now, and I haven't had much luck. I've messed with Control.Region, Form.TransparencyKey, Form.Opacity, and a couple other random things with some funky effects.
Lately I've been trying to customize my desktop and decided to mess with Application Docks. After seeing what the Mac dock and a few third-party Windows implementations had to offer, I decided I wanted to build my own.
Eventually I want to move on to using the Win32 API. For now I just want to get something working using as much C# and .Net framework capabilities as possible.
There are a few things I want to be able to do in this application:
Display a form/menu with a gradient background.
Allow the form/menu to have transparency while keeping icons opaque.
Display icons that contain transparent backgrounds.
The Menu and Icons should be able to receive mouse-related events (hover, leave, click, dragover, dragdrop, and a few others).
This is the effect I'm shooting for:
http://img207.imageshack.us/img207/5716/desired.jpg
This image shows the visual effects I'm trying to achieve. This was a skin I made for a program called Rainmeter. The image shows Notepad++ behind the skin with a few of the skin's files open in the editor. The menu is transparent, but the icons remain opaque.
My Approach:
Using a Form to act as the menu seemed like a logical first choice to me. I have a basic understanding of events. I'm not quite sure how to create my own click events, so a form would make working with events a tad easier. I considered a few options for the icons. I decided I'd use PictureBoxes for the icons, since they can hold images and receive events.
Once I finished the code for all the structural logic of my menu, I started playing around with it to try to get the visual effect I wanted. Form.Opacity affected the transparency of everything on the form. Since I want the icons to be fully opaque, I left this property alone. I tried setting the BackColor to Color.Transparent, but that gives an error. I played around with a few combinations...
http://img204.imageshack.us/img204/757/effectsi.jpg
I drew the gradient with a Drawing2D.LinearGradientBrush into a Bitmap. This Bitmap was then placed as the Form.BackgroundImage or as a PictureBox.Image. If used, the PictureBox was sized to cover the entire Form and sent to the back.
I noticed that some of the Form.BackgroundColor would be mixed in with the outlines of my icons. The icons have transparency along the edges for a smoother appearance. Since the icons are picking up the Form's BackgroundColor, this makes me think that the PictureBoxes are creating new images when the icons are loaded into the form. The semi-transparent portions of the image are then merged with the Form's BackgroundColor when they should merge with whatever colors are behind the form.
http://img838.imageshack.us/img838/8299/whitedesktop.jpg
In this image you can see the Fuchsia existing in the icons even though the Form's Fuchsia color is now completely transparent. I forgot to point out that the same green to yellow gradient with an Alpha value of 150 was used in every case. In the images where the gradient doesn't look green, it's because the transparent colors are blending with the Fuchsia background.
I'm not really sure what to do from here. I feel like I could get what I want if I could somehow make the Form alone completely transparent. I was also thinking I may have better luck just drawing the icons instead of using PictureBoxes. The problem then would be setting up the icons to receive mouse events. (I've never made my own events, and I think it would involved some Win32 API calls.)
Is there something else I can do with the PictureBoxes to get the effect I want? Whichever the case, I'm open to any ideas or suggestions for the overall effect I'm trying to achieve.
This is pretty easy to do in Winforms. What you need is a sandwich of two forms. The bottom one should provide the transparent gradient background, the top one should draw the icons and handle mouse clicks. Some sample code:
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
this.TopMost = true;
this.FormBorderStyle = FormBorderStyle.None;
this.TransparencyKey = this.BackColor = Color.Fuchsia;
this.Opacity = 0.3;
var overlay = new Form();
overlay.FormBorderStyle = FormBorderStyle.None;
overlay.TransparencyKey = overlay.BackColor = Color.Fuchsia;
overlay.StartPosition = FormStartPosition.Manual;
overlay.Location = this.Location;
overlay.MouseDown += HandleIconClick;
this.Resize += delegate { overlay.Size = this.Size; };
this.LocationChanged += delegate { overlay.Location = this.Location; };
overlay.Paint += PaintIcons;
this.Paint += PaintBackground;
this.Load += delegate { overlay.Show(this); };
}
private void PaintBackground(object sender, PaintEventArgs e) {
var rc = new Rectangle(0, 0, this.ClientSize.Width, this.ClientSize.Height);
using (var br = new LinearGradientBrush(rc, Color.Gainsboro, Color.Yellow, 0f)) {
e.Graphics.FillRectangle(br, rc);
}
}
private void PaintIcons(object sender, PaintEventArgs e) {
e.Graphics.DrawIcon(Properties.Resources.ExampleIcon1, 50, 30);
// etc...
}
void HandleIconClick(object sender, MouseEventArgs e) {
// TODO
}
}
Which looks like this with the somewhat random colors and icon I selected:
OK, I got a bit lost in all that, but from the description in the original paragraph, I would make sure the background rectangle is NOT the visual parent of the pictureboxes. Make them overlapping siblings, with the pictureboxes in front using Panel.Zindex.
Then you can just change the opacity of the rectangle, without affecting the icons. Also make sure the icon source image files have a transparent background.
Should work I think.
I have drawn a circle in windows form
Pen pen = new Pen(Color.Black, 3);
Graphics gr = this.CreateGraphics();
gr.DrawEllipse(pen, 5,5,20,20);
How to delete it...
You have to clear your Graphic:
Graphics.Clear();
But all drawn figures will be cleared. Simply, you will then need to redraw all figures except that circle.
Also, you can use the Invalidate method:
Control.Invalidate()
It indicates a region to be redrawn inside your Graphics. But if you have intersecting figures you will have to redraw the figures you want visible inside the region except the circle.
This can become messy, you may want to check out how to design a control graph or use any graph layout library.
You can invalidate the draw region you want to refresh for example:
this.Invalidate();
on the form...
Assuming you're subscribing to the Paint event or overriding the protected OnPaint routine, then you will need to perform something like this:
bool paint = false;
protected override void OnPaint(object sender, PaintEventArgs e)
{
if (paint)
{
// Draw circle.
}
}
Then when you want to stop painting a circle:
paint = false;
this.Invalidate(); // Forces a redraw
You can make a figure of same dimensions using the backColor of your control in which you are drawing
use after your code to clear your figure.
Pen p = new Pen(this.BackColor);
gr.DrawEllipse(p, 5,5,20,20);
In fact, you can delete your circle and nothing but your circle.
Everything you need is something like a screenshot of the "before state" of the area you want to clear, to make a TextureBrush from it. You can achieve that step by something like this:
Bitmap _Background = new Bitmap(this.Width, this.Height);
Graphics.FromImage(_Background).CopyFromScreen(this.Left, this.Top, 0, 0, this.Size);
The first line will give you a bitmap in your windows forms size. The second line will save a screenshot of it in the _Background-bitmap.
Now you create a TextureBrush out of it:
Brush brsBackground = new TextureBrush(_Background);
The next thing you need are the dimensions of your circle, so you should save them into a variable, if they are not a fix value. When you got them at hand, you can clear the specific area like this:
Graphics gr = this.CreateGraphics();
gr.FillEllipse(brsBackground, 5, 5, 20, 20); // values referred to your example
Done!
Even complex figures are able to be deleted by this, like a GraphicsPath for example:
GraphicsPath gp = new GraphicsPath(); // any kind of GraphicsPath
gr.FillRegion(brsBackground, new Region(gp));
You don't "delete" it per se, there's nothing to delete. It's a drawing, you draw something else over it or you can call the Graphics.Clear() method.
If u are using Invalidate() and is not working, make a panel.Refresh().
That will work on you.
just make another control with the attributes etc. that you want, make the visibility to false and set the region of the control to the other control like this:
pen.Region = pen2.Region;
It is very simple to delete a drawn circle from c.
There is only four steps:-
Open turbo app
go to the command where you had drawn the circle
drag the command
click on delete button